Means for supporting and driving tubular grinding mills



April 2 1 F. R. BARRATT MEANS FOR SUPPORTING ANDDRIVING TUBULAR GRINDING MILlLS Filed March 22, 1934 s Sheets-Shet l A ril 27, 1937.

MEANS FOR SUPPORTING AND DRIVING TUBULAR GRINDING MILLS F. R. BARRATT 2,078,82

Filed March 22, 1934 3 Shets-Sheet 2 April 27, 1937. F, R; BARRATT 2,078,829

MEANS FOR SUPPORTING AND DRIVING TUBULAR GRINDING MILLS Filed March 22, 1934 3 Sheets-Sheet 3 Patented Apr. 27, 1937 MEANS FOR SUPPORTING AND DRIVING TUBULAR GRINDING BULLS Frederick Reeves Barratt, Krugersdorp, Transvaal, Union of South Africa Application March 22, 1934, Serial No. 716,868 In Union of South Africa November 11, 1933 1 Claim.

This invention relates to means for supporting and driving tubular grinding mills. This application shows and describes various features which are claimed in a companion application 5 Serial No. 716,867, filed of even date herewith.

According to the invention there is provided a chassis upon which are erected the means for rotatably supporting the mill drum and the means for rotating it. The operative mill structure thus constitutes a single unit which can be supplied complete to the user and requires little or no foundation to be provided. It is moreover portable as compared mm the usual rotary grinding mill, which is supported by means of its trunnions upon concrete pillars and the driving gear of which is secured upon separate foundations.

The invention is illustrated in the accompanying drawings in which:

Figures I and II are respectively a side and end elevation of one form of the invention.

Figures III and IV are similar views of another form.

Figures V and VI are similar views of a third form.

In all of the figures the grinding mill proper comprises a barrel 2, ends 3, 4 and orifices 5 and 8 in the ends for receiving material to be ground and for discharging the ground material. The chassis 1 consists of a framework of structural steel having a plane under surface 8, which permits it to be stood solidly on level ground.

In Figures I and II the means for rotatably supporting the mill comprises at one end of the mill a hollow trunnion 9 formed on the end cover 3. Said trunnion is carried in a bearing ii! supported on a pillar H which in turn is erected on the chassis l. The bearing it; is of the known kind which permits small deviation of the axis of the mill from its normal position. The rotary supporting means further comprises the belts l2 hung from pulleys l3 and engaging treads it on the barrel 2 of the mill. The pulleys l3 are fast on a shaft l5 mounted in bearings It which rest on a frame ll, [8. Said frame is supported and adapted for vertical adjustment by means of screw jacks l9 resting on framework 2t, 2! mounted on posts 22 erected on the chassis 'l.

The end of the mill opposite the trunnion 9 is. further supported in a roller cradle comprising two rollers 23 positioned to engage the underside of a roller path 24 formed on the barrel and thereby prevent the barrel from swinging laterally. Said rollers may, if desired, be caused to 55 take a portion of the weight of the barrel by suitably adjusting the jacks it so that only'part of the weight is taken by the belts l2.

In the form shown in Figures III and IV the barrel is supported Wholly by means of a roller cradle which in this case comprises at least four rollers 23. In order to control the mill against lengthwise displacement the roller paths 24 on the barrel are provided with end flanges 25 or equivalent flanges are formed on the rollers. It is evident that the roller cradle so supports the barrel that it is freely rotatable about its axis 26. Figures V and VI show the barrel supported jointly by belts if as in Fi ures I and II and by a four-roller cradle 23 as in Figures III and IV.

Various means for rotating the drum may be employed. Figures III and IV show the barrel, fitted with a spur ring 21. The latter meshes with a pinion 28 fixed on a countershaft Z9. Said shaft is mounted in bearings 36 carried on the chassis 7 and is fitted with a pulley 3! by means of which it is driven from any convenient source of power.

Figures I, II, V and VI show the drum driven by the suspending belts l2. For this purpose the shaft I5 is provided with any suitable means for rotating it, such as the spur gear 3! engaged by the pinion 32. The latter is mounted on a coun tershaft 33 which is itself driven by means of a belt on the pulley 34.

The frame 2B, 2! which carries the jacks l9 and is supported on. the posts 22. provides a convenient means for supporting a roof which protects the mill and the mill operator. The cross members 26 of said frame are for this purpose extended far enough to carry roof frame members 35 sloped towards one another at a proper angle to clear the gear 3!, 32 and adjacent parts. Said members 35 support the roofings 36. To steady the structure the ends of the members 26 are provided with downwardly extended legs 31pmvided with feet 38 which can simply rest on the ground or can be secured to a foundation if desired.

The cross members 26 are extended well beyond the frame proper, and said members 20, 2| constitute gantries or elevated supports for tackle used for handling heavy parts of the apparatus such as the mill ends 34. The posts 22 on at least one side of the mill are bolted to the chassis l and the frame 29, 2!, and the roller brackets 39 at one side of the mill are similarly bolted to the chassis, so that said posts and brackets may be taken down without difficulty to enable the mill barrel to be removed when required for repair or the like, and replaced.

I claim:

A wet grinding tube mill suitable for comminuting ores, comprising a rotatable barrel, a chassis constructed as a flat frame composed of several structural steel members having their under surfaces level with one another so as to form a plane under surface for the chassis and thereby providing a foundation for the mill structure, metal posts erected on the chassis, a framework supported by said posts, auxiliary means for supporting said framework, a shaft on the framework, means for driving the shaft, pulleys on the shaft, flexible members hung from the pulleys and suspending the barrel, and roller cradle members mounted on the chassis for contacting with the barrel, some of said posts at one side of the barrel being removably secured to the chassis and the framework, and the roller cradle elements on the same side being removably secured to the chassis, so that upon displacement of said removable elements the barrel may be removed and replaced laterally while the auxiliary frame supporting means functions in place of the re- 10 moved posts.

FREDERICK REEVES BARRATT. 

